The family of synthetic hydrophilic polymers includes polyacrylic acid, polyvinyl pyrrolidone, polyvinyl alcohol, polyacrylamide, poly hydroxybutyl acrylate, and poly 2-hydroxyethyl methacrylate. In this family of synthetic hydrophilic polymers, poly 2-hydroxyethyl methacrylate and poly hydroxybutyl acrylate are water insoluble polymers prepared from a water soluble monomer. The other polymers require crosslinking to form a water insoluble polymer.
2-Hydroxyethyl methacrylate polymers are of interest because of their biocompatibility, as evidenced by excellent performance in animal implant studies. The extensive use of 2-hydroxyethyl methacrylate polymers for contact lenses for the eyes illustrates the non irritating nature of the polymers.
Other than commercial use in contact lenses, 2-hydroxyethyl methacrylate polymers have had limited commercial success, used at low percentages only, because of the nature of the monomer. Industrial grade 2-hydroxyethyl methacrylate monomer contains a small amount of crosslinker impurity which can cause gel formation during solvent polymerization. The 2-hydroxyethyl methacrylate monomer is water soluble and the 2-hydroxyethyl methacrylate polymer is water insoluble which causes difficulty in emulsion polymerization employing a high portion of 2-hydroxyethyl methacrylate monomer. The preparation of 2-hydroxyethyl methacrylate polymer therefore generally requires the use of very pure and expensive monomer, having ethylene glycol dimethacrylate impurities less than 0.035 weight percent, based on the weight of the monomer, or a very extensive and expensive polymerization process.
Requirements of high quality inkjet coatings include clarity, water resistance, good ink absorption with quick drying, and low surface friction to enhance sheet feeding in inkjet printers. Typical inkjet coatings satisfy the requirements of water resistance, good ink absorption with quick drying, and low surface friction through the use of mixtures of polymers, or polymers with pigments, however, these mixtures are not clear.
U.S. Pat. No. 2,976,576 describes the use of poly 2-hydroxyethyl methacrylate resin for contact lenses and body implants.
U.S. Pat. No. 3,220,960 describes the use of poly 2-hydroxyethyl methacrylate resin for contact lenses and body implants.
U.S. Pat. No. 3,567,760 describes the preparation of 2-hydroxyethyl methacrylate copolymers in methanol that are water soluble salts for entrapping drugs, pesticides, flavoring agents, and fragrances.
U.S. Pat. No. 3,963,685 describes the preparation of methanol soluble poly 2-hydroxyethyl methacrylate for wound care dressings using high purity 2-hydroxyethyl methacrylate monomer having not over 0.035 weight percent of alkylene glycol dimethacrylate impurities.
EP 024164A1 describes the preparation of methanol soluble poly 2-hydroxyethyl methacrylate using high purity 2-hydroxyethyl methacrylate monomer.
Polymer International, vol. 36 no. 4, pp.303–308 (April 1995), describes the preparation of dimethylformamide soluble poly 2-hydroxyethyl methacrylate using a chain transfer agent to prevent gellation.
U.S. Pat. No. 4,303,066 describes the use of a plasticized poly 2-hydroxyethyl methacrylate resin prepared from high purity monomer as a non-tacky synthetic film for skin burns, with shortened forming time by adding water to the mixture.
U.S. Pat. No. 4,593,053 describes the use of a plasticized polyvinyl pyrrolidone as a hydrophilic medical type pressure sensitive adhesive for biomedical electrodes and transdermal devices.
WO 92/11825 describes the use of plasticized poly 2-hydroxyethyl methacrylate resin as a hydrophilic medical type pressure sensitive adhesive for a medical device.
U.S. Pat. No. 5,225,473 describes the use of a UV cured plasticized polyvinyl pyrrolidone as a hydrophilic medical type pressure sensitive adhesive for biomedical electrodes and transdermal devices.
U.S. Pat. No. 4,892,787 describes coated paper for inkjet printing containing pigment, an acrylic emulsion, and a water soluble polymer.
U.S. Pat. No. 5,206,071 describes acrylic graft copolymers and water soluble polymers.
U.S. Pat. No. 5,478,631 describes an inkjet recording sheet using a pigment and an amphoteric ion latex.
EP 0716929A1 describes acrylic graft copolymers and water soluble polymers.
DE 19516111A1 describes water soluble copolymers with crosslinkers.
U.S. Pat. No. 5,672,392 describes the preparation of recording materials for inkjet printers using acrylic emulsions and water soluble polymers.
U.S Pat. No. 3,813,695 discloses a rubber or latex surgical glove that is laminated with an internal lining of a hydrophilic material.
U.S. Pat. No. 4,575,476 discloses a dipped rubber glove having an outer rubber layer and a lubricating layer formed of a hydrogel polymer bonded thereto to provide a skin-contacting surface of the glove.
In general, the present invention is directed to providing a cost-effective method for the preparation of hydrophilic 2-hydroxyethyl methacrylate homopolymers and copolymers with utility as films, coatings, pressure sensitive adhesives, and compositions suitable for topical application to the skin.
The present invention is further directed to providing clear inkjet coatings without pigments that are water resistant and have good ink absorption with quick drying.
The invention is also related to providing a cost-effective method for the preparation of gel-free, hydrophilic polymers, which have utility in topical skin applications, as cosmetic compositions, dermatological compositions, and as skin friendly coatings, as pressure sensitive adhesives, and as precursors for hydrogels.